On Mon, Feb 01, 2021 at 03:49:52PM -0500, Dai Ngo wrote:
> Fix by returning -EINVAL instead of 0, per man page of copy_file_range,
Huh? That's not what the manpage[1] says:
RETURN VALUE
Upon successful completion, copy_file_range() will return the
number of bytes copied between files. This could be less than the
length originally requested. If the file offset of fd_in is at or past
the end of file, no bytes are copied, and copy_file_range() returns
zero.
--D
[1] https://man7.org/linux/man-pages/man2/copy_file_range.2.html#RETURN_VALUE
> when the requested range extends beyond the end of the source file.
> Problem was discovered by subtest inter11 of nfstest_ssc.
>
> Signed-off-by: Dai Ngo <dai.ngo@xxxxxxxxxx>
> ---
> fs/read_write.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/read_write.c b/fs/read_write.c
> index 75f764b43418..438c00910716 100644
> --- a/fs/read_write.c
> +++ b/fs/read_write.c
> @@ -1445,7 +1445,7 @@ static int generic_copy_file_checks(struct file *file_in, loff_t pos_in,
> /* Shorten the copy to EOF */
> size_in = i_size_read(inode_in);
> if (pos_in >= size_in)
> - count = 0;
> + count = -EINVAL;
> else
> count = min(count, size_in - (uint64_t)pos_in);
>
> --
> 2.9.5
>
